iW- 14s 



THE LEAF-SPOTS OF ARUM MACULATUM. 



BY GKORGE H. PETHYBRIDGE, PH.D., B.SC 



A PROPOS of Mr. Colgan's article on this subject in the March 

 number of the /rts/i Naturalist, a few notes which I have 

 collected may be worth putting on record. With regard to 

 the relative distribution ot the spotted and the unspotted 

 forms on the Continent, I may add to the French and German 

 authorities, quoted by Mr. Colgan, a Dutch and the two 

 principal Belgian authorities. Devos in his Flore de la 

 Belgique, 1885, says that the leaves are often spotted with 

 black {souvent tachees de 7ioir), and Crepin in his Ma7tuel de la 

 flore de Belgique, 1884, says that the leaves are green, or 

 spotted with black {Feuilles .... vertes et concolorcs ou 

 maculees de noir). Hall, in his Neerla^ids Plantc7ischat, 1854, 

 speaks of the ordinary spotted Arum {zooals in de gewo7ie of 

 gevlekte Aro7iskelk). 



Stahl, in a most interesting paper on coloured foliage-leaves,^ 

 states, however, on the authority of Ascherson {Flora der 

 Provi7iz Bra7ide7ibur^), that in this province the leaves are 

 always spotted ; whereas, according to Kirchner {Flora von 

 St2ittgart und U7}igebu7ig), in Wiirtemburg the leaves are 

 never spotted. 



As regards the distribution of the two forms in Great 

 Britain, I was under the impression that in Cornwall and 

 Devonshire, at any rate, the spotted form was the more 

 common of the two ; but not having spent time in the spring 

 in either of these counties for some 3'ears, I wrote to a 

 botanical friend living in mid-Cornwall for information. He 

 replied that his impression was the same as mine, but that he 

 would make observations on the point. These observations 

 resulted in establishing the fact that the green unspotted 

 form was by far the more common, and that the spotted form 

 was comparatively scarce. So much for the value of im- 

 pressions ! In order to obtain further information, 1 addressed 



^ E. Stahl Ueber bunte Laubblatter. AnnaUs du Jardin Botauique 



de Buileuzorg, t. XIIL, 1896. 



